title: No significant association between the alpha-2A-adrenergic receptor gene and treatment response in combined or inattentive subtypes of attention-deficit hyperactivity disorder.
abstract: BACKGROUND
  Given the shortage of pharmacogenetic studies on treatment response according to subtype of attention-deficit hyperactivity disorder (ADHD), we investigated the associations between the MspI and DraI polymorphisms of the alpha-2 A-adrenergic receptor gene (ADRA2A) and treatment response to methylphenidate according to subtype of ADHD.
  
  
  METHODS
  We enrolled 115 medication-naïve children with ADHD into an open label 8-week trial of methylphenidate. The participants were genotyped and evaluated using the Clinical -Global Impression (CGI), ADHD rating scale, and Continuous Performance Test (CPT) pre- and post-treatment.
  
  
  RESULTS
  There was no statistically significant association between the MspI or DraI genotypes and the relative frequency of CGI-improvement (CGI-I) 1 or 2 status among any of the groups (all types of ADHD, ADHD-C, or ADHD-I). However, among the children with ADHD-C, those subjects with the C/C genotype at the ADRA2A DraI polymorphism tended to have a CGI-I 1 or 2 status post-treatment (OR=4.45, p=0.045).
  
  
  CONCLUSIONS
  The results of this study do not support the association between the the MspI or DraI genotypes and treatment response to methylphenidate in ADHD. However, our results -suggest that subtypes might influence pharmacogenetic results in ADHD.·available online at http://www.thieme-connect.de/ejournals/toc/pharmaco.
authors.affiliation: Division of Child and Adolescent Psychiatry, Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: S
authors.initials: S
authors.lastname: Park
authors.forename: J-W
authors.initials: JW
authors.lastname: Kim
authors.forename: B-N
authors.initials: BN
authors.lastname: Kim
authors.forename: S-B
authors.initials: SB
authors.lastname: Hong
authors.forename: M-S
authors.initials: MS
authors.lastname: Shin
authors.forename: H-J
authors.initials: HJ
authors.lastname: Yoo
authors.forename: S-C
authors.initials: SC
authors.lastname: Cho
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000188:drug therapy* / Q000235:genetics*; D002648:Child; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008774:Methylphenidate / Q000627:therapeutic use*; D009483:Neuropsychological Tests; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D018341:Receptors, Adrenergic, alpha-2 / Q000235:genetics*; D016896:Treatment Outcome
chemical_list: D018341:Receptors, Adrenergic, alpha-2; D008774:Methylphenidate